[Patch v2 2/3] thermal: hisilicon: add thermal sensor driver for Hi3660

[Tao Wang <kevin.wangtao@hisilicon.com>]

This patch adds the support for thermal sensor of Hi3660 SoC.
this will register sensors for thermal framework and use device
tree to bind cooling device.

Signed-off-by: Tao Wang <kevin.wangtao@hisilicon.com>
Signed-off-by: Leo Yan <leo.yan@linaro.org>
---
Changes in v2:
- correct alphabet order
- correct compatible name

 drivers/thermal/Kconfig          |   10 ++
 drivers/thermal/Makefile         |    1 +
 drivers/thermal/hi3660_thermal.c |  198 ++++++++++++++++++++++++++++++++++++++
 3 files changed, 209 insertions(+)
 create mode 100644 drivers/thermal/hi3660_thermal.c

diff --git a/drivers/thermal/Kconfig b/drivers/thermal/Kconfig
index b5b5fac..ed22a90 100644
--- a/drivers/thermal/Kconfig
+++ b/drivers/thermal/Kconfig
@@ -192,6 +192,16 @@ config THERMAL_EMULATION
 	  because userland can easily disable the thermal policy by simply
 	  flooding this sysfs node with low temperature values.
 
+config HI3660_THERMAL
+	tristate "Hi3660 thermal driver"
+	depends on ARCH_HISI || COMPILE_TEST
+	depends on HAS_IOMEM
+	depends on OF
+	default y
+	help
+	  Enable this to plug Hi3660 thermal driver into the Linux thermal
+	  framework.
+
 config HISI_THERMAL
 	tristate "Hisilicon thermal driver"
 	depends on ARCH_HISI || COMPILE_TEST
diff --git a/drivers/thermal/Makefile b/drivers/thermal/Makefile
index 094d703..f29d0a5 100644
--- a/drivers/thermal/Makefile
+++ b/drivers/thermal/Makefile
@@ -55,6 +55,7 @@ obj-$(CONFIG_INTEL_PCH_THERMAL)	+= intel_pch_thermal.o
 obj-$(CONFIG_ST_THERMAL)	+= st/
 obj-$(CONFIG_QCOM_TSENS)	+= qcom/
 obj-$(CONFIG_TEGRA_SOCTHERM)	+= tegra/
+obj-$(CONFIG_HI3660_THERMAL)	+= hi3660_thermal.o
 obj-$(CONFIG_HISI_THERMAL)     += hisi_thermal.o
 obj-$(CONFIG_MTK_THERMAL)	+= mtk_thermal.o
 obj-$(CONFIG_GENERIC_ADC_THERMAL)	+= thermal-generic-adc.o
diff --git a/drivers/thermal/hi3660_thermal.c b/drivers/thermal/hi3660_thermal.c
new file mode 100644
index 0000000..68fa9018
--- /dev/null
+++ b/drivers/thermal/hi3660_thermal.c
@@ -0,0 +1,198 @@
+/*
+ *  linux/drivers/thermal/hi3660_thermal.c
+ *
+ *  Copyright (c) 2017 Hisilicon Limited.
+ *  Copyright (c) 2017 Linaro Limited.
+ *
+ *  Author: Tao Wang <kevin.wangtao@hisilicon.com>
+ *  Author: Leo Yan <leo.yan@linaro.org>
+ *
+ *  This program is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation; version 2 of the License.
+ *
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <linux/clk.h>
+#include <linux/device.h>
+#include <linux/err.h>
+#include <linux/io.h>
+#include <linux/kernel.h>
+#include <linux/of.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/thermal.h>
+
+#include "thermal_core.h"
+
+#define HW_MAX_SENSORS			4
+#define HISI_MAX_SENSORS		6
+#define SENSOR_MAX			4
+#define SENSOR_AVG			5
+
+#define ADC_MIN		116
+#define ADC_MAX		922
+
+/* hi3660 Thermal Sensor Dev Structure */
+struct hi3660_thermal_sensor {
+	struct hi3660_thermal_data *thermal;
+	struct thermal_zone_device *tzd;
+
+	uint32_t id;
+};
+
+struct hi3660_thermal_data {
+	struct platform_device *pdev;
+	struct hi3660_thermal_sensor sensors[HISI_MAX_SENSORS];
+	void __iomem *thermal_base;
+};
+
+unsigned int sensor_reg_offset[HW_MAX_SENSORS] = { 0x1c, 0x5c, 0x9c, 0xdc };
+
+
+static int hi3660_thermal_get_temp(void *_sensor, int *temp)
+{
+	struct hi3660_thermal_sensor *sensor = _sensor;
+	struct hi3660_thermal_data *data = sensor->thermal;
+	unsigned int idx;
+	int val, average = 0, max = 0;
+
+	if (sensor->id < HW_MAX_SENSORS) {
+		val = readl(data->thermal_base + sensor_reg_offset[sensor->id]);
+		val = clamp_val(val, ADC_MIN, ADC_MAX);
+	} else {
+		for (idx = 0; idx < HW_MAX_SENSORS; idx++) {
+			val = readl(data->thermal_base
+					+ sensor_reg_offset[idx]);
+			val = clamp_val(val, ADC_MIN, ADC_MAX);
+			average += val;
+			if (val > max)
+				max = val;
+		}
+
+		if (sensor->id == SENSOR_MAX)
+			val = max;
+		else if (sensor->id == SENSOR_AVG)
+			val = average / HW_MAX_SENSORS;
+	}
+
+	*temp = ((val - ADC_MIN) * 165000) / (ADC_MAX - ADC_MIN) - 40000;
+
+	return 0;
+}
+
+static struct thermal_zone_of_device_ops hi3660_of_thermal_ops = {
+	.get_temp = hi3660_thermal_get_temp,
+};
+
+static int hi3660_thermal_register_sensor(struct platform_device *pdev,
+		struct hi3660_thermal_data *data,
+		struct hi3660_thermal_sensor *sensor,
+		int index)
+{
+	int ret = 0;
+
+	sensor->id = index;
+	sensor->thermal = data;
+
+	sensor->tzd = devm_thermal_zone_of_sensor_register(&pdev->dev,
+				sensor->id, sensor, &hi3660_of_thermal_ops);
+	if (IS_ERR(sensor->tzd)) {
+		ret = PTR_ERR(sensor->tzd);
+		sensor->tzd = NULL;
+	}
+
+	return ret;
+}
+
+static void hi3660_thermal_toggle_sensor(struct hi3660_thermal_sensor *sensor,
+				       bool on)
+{
+	struct thermal_zone_device *tzd = sensor->tzd;
+
+	tzd->ops->set_mode(tzd,
+		on ? THERMAL_DEVICE_ENABLED : THERMAL_DEVICE_DISABLED);
+}
+
+static int hi3660_thermal_probe(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	struct hi3660_thermal_data *data;
+	struct resource *res;
+	int ret = 0;
+	int i;
+
+	data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL);
+	if (!data)
+		return -ENOMEM;
+
+	data->pdev = pdev;
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	data->thermal_base = devm_ioremap_resource(dev, res);
+	if (IS_ERR(data->thermal_base)) {
+		dev_err(dev, "failed get reg base\n");
+		return -ENOMEM;
+	}
+
+	platform_set_drvdata(pdev, data);
+
+	for (i = 0; i < HISI_MAX_SENSORS; ++i) {
+		ret = hi3660_thermal_register_sensor(pdev, data,
+						     &data->sensors[i], i);
+		if (ret)
+			dev_err(&pdev->dev,
+				"failed to register thermal sensor%d: %d\n",
+				i, ret);
+		else
+			hi3660_thermal_toggle_sensor(&data->sensors[i], true);
+	}
+
+	dev_info(&pdev->dev, "Thermal Sensor Loaded\n");
+	return 0;
+}
+
+static int hi3660_thermal_exit(struct platform_device *pdev)
+{
+	struct hi3660_thermal_data *data = platform_get_drvdata(pdev);
+	int i;
+
+	for (i = 0; i < HISI_MAX_SENSORS; i++) {
+		struct hi3660_thermal_sensor *sensor = &data->sensors[i];
+
+		if (!sensor->tzd)
+			continue;
+
+		hi3660_thermal_toggle_sensor(sensor, false);
+	}
+
+	return 0;
+}
+
+static const struct of_device_id hi3660_thermal_id_table[] = {
+	{ .compatible = "hisilicon,hi3660-thermal" },
+	{}
+};
+MODULE_DEVICE_TABLE(of, hi3660_thermal_id_table);
+
+static struct platform_driver hi3660_thermal_driver = {
+	.probe = hi3660_thermal_probe,
+	.remove = hi3660_thermal_exit,
+	.driver = {
+		.name = "hi3660_thermal",
+		.of_match_table = hi3660_thermal_id_table,
+	},
+};
+
+module_platform_driver(hi3660_thermal_driver);
+
+MODULE_AUTHOR("Tao Wang <kevin.wangtao@hisilicon.com>");
+MODULE_AUTHOR("Leo Yan <leo.yan@linaro.org>");
+MODULE_DESCRIPTION("hi3660 thermal driver");
+MODULE_LICENSE("GPL v2");
-- 
1.7.9.5